Carburetor



Sept. 14. 1926.

F. O. BALL' CARBURETOR Filed Juxle 10, 1919 @mue/Mofa Patented Sept. 14, 1926.'

`Uru'rliz STAT-Es Aamizu'r OFFICE.

FREDERICK O. BALL, 0F DETROIT, MICHIGAN, ASSIGNOR TOBALL 65 DALL CARBU- RETOR COMPANY, 0F DETROIT, MICHIGAN, A PARTNEBSHXI COMPOSED OF FRED- ERICE` 0. BALL AND CQRNELI M. BALL. I

marcharon.

Application med :rune 1o, 1919. serial No. sos-,aos

In the operation of ra carburetor it is dei sirable to get suflicient velocity of airv through the suction passage to atomize the,

fuel- Vith a wide open throttle and a rapid speed of the engine' there is a sufficient velocity of the air through the contracted portion of the suction passage, usually inthe form of a Venturi tube to accomplish this purpose. When there is a slower speed ,of the engine with a partially closedv throttle there is a suflicient yvelocity of air past the throttle to accomplish the purpose. In one instance the restriction is at the lVenturi tube. and in the other instance the restriction is made by the throttle. Where, however, there is a Wide open throttle and `a vslow movement of the motor as is apt to be the condition on a hill Withan automobile there isnot suliicient velocity of air through the carburetor to properly atomize the fuel. In addition to this the mixture is not usually' suliciently rich to lgive the maximum povver so that there is a lack of a suliciently rich mixture to give maximum power even though the atomization were complete, which condition is aggravated by a lack of atom1 zation so that the ultimate result is that for all practical purposes, a leaner mixture 1s provided than the mixture delivered under other conditions. Itis desirable, therefore, to suppplement the normal fuel supply where there is a slow movement of air throughl the suction passage so as to give .the most ellicient mixture under these condltions. If this can be attained automatically `a very lean mixture may. be provided for other working conditions so that there will be an economy of fuel as Well as a satisfactory performance under the varying conditions above mentioned. With the present invention this is accomplished. The invention is illustrated in the accompanying drawing wherein a carburetor .is shown in vertical section.

1 marks the suction passage, 2 the throttle,

y 3 the Venturi tube, f1 vfuel nozzles which as shown project from the walls of the Venturi tube, 5 an annular chamber around the Venturi tube and from which the fuel nozzles lead 6 a passage connecting the annular chamber 5 with an intermediate chamber `7 formed between the Walls of a socket 8 formed in the body ofthe carburetor and the Walls of a metering plug 9. The metering plug has a metered fuel opening 1G which leads to a passage 11 in the plug and the passage 11 communicates with the chamber 7 by means of a radial passage 12. `A fuel passage 13 leads from a float chamber 14 to the metered opening 10. The float chamber has the usu'alsupply connection 15 f negative head necessar Where the fuel is delivered in the form o raw fuel to the nozzle. Air is admitted to the passage 18 through a passage 19 in the plug 9.- A restricted opening 20 communicates with the passages 18 and 11. A passage 21 also leads from the passa e 18 to the chamber 7. With the passa es a mitting air to the chambers between tie "fuel restriction 10 and the nozzles 4 the suction at the metered opening 10 follows the suction of the suction passage but this suction is reduced by the introduction of the air. The fuel level is indicated at A-A. The fuel level is approximately forth are as :follows: The chamber 7 is connected with a passage or chamber 22 by a passage 23. The chamber 22 opens to the atmosphere and is controlled by a. valve 24. The valve 24 has a stem 25 which terminates in a piston 26. The piston operates ima cylinder 27. The cylinder is connected by a passa e 28 with the suction passage ata point a ve the throttle. A spring 29 is arrangedon the stem 25 and operates against lL passage communicating with the suction pasa shoulder 30 on the stem 25 and rests against a shoulder 31 at the end `of the cylinder 27. The spring is of sufficient strength to re tain the valve 24 in closed position until there is such a preponderance of pressure below the piston 26 as to overcome the spring and open theY valve. n

When there is a wide open throttle and a slow running motor there is, of course, very little reduction of pressure in the suction passage and consequently a very small reduc# tion of pressure in the cylinder 27. Consequently the preponderance of atmospheric pressure over suction passage pressure is not sufficient to overcome the spring 29 so as to open the valve 24. The valve 24 remains in a closed osition and the reduction in pressure in t e passage 1l inducing a flow through the metered opening l() is a pressure between that of the Venturi tube' and the atmosphere depending on the size of the openings admitting air into the passage l1 and the size of the nozzles forming a means of communication between the passage 11 and the Venturi tube. These are so proportioned as to give a comparatively rich mixture so that the mixture is better adapted to the higher power desired under such conditions but more particularly it supplements the fuel so as to make up for the lack of atomization. When, however, the motor, speeds up or a speed is maintained with a partially closed `throttle so that there is a higher velocit at the restrictions of the suction passage t ere is a corresponding reduction of pressure at the discharge side of the throttle which is communicated through the passage 28 to the cylinder 27 and a consequent reduction` of pressure above the piston 26 creates a preponderance of pressure below the piston which overcomes the spring 29 and lifts the valve 24, the amount of the opening being dependent on the degree of reduction of pressure.

As the valve y24 is opened air is admitted to the passage or chamber 7 and communicated tothe passage 11 so that the reduction I of pressure 1n the passage 11 is less and in consequence the suction effort on the fuel at the restricted opening 10 is reduced, with a consequent reduction in the quantity of fuel delivered. In addition there is a slight- 1 greater amount of air delivered through t e nozzles 4 which also tends to make a leaner mixture.

In the drawings I have shown the parts at rest. In operation the closing of the throttle opens the valve 24. It will be understood that the fuel in the chamber 6 is ordinarily swept out by the air to the level of the vfloor of said chamber.

What I claim as new is 1. In a carburetor, the combination of a Y suction passage having an air intake; a fuel sage the atmosphere and a source of fuel su ply, said fuel passage delivering fuel to t e suction passage; and devices varying the' air supply to the fuel passage to vary the flow of fuel, said devices acting only with a predetermined reduced pressure inthe suction passage and continuing-to act during such variation of pressure to enrich the mixture with such reduced suction.

2. In a carburetor, the combination of a suction passage having an air intake; a fuel passage communicating with the suction passage the atmosphere and a source of fuel supply, said fuel passage delivering at least the major portion of the fuel to the suction passage; and devices varying the air supply to vary the flow of fuel, said devices acting only with a predetermined reduced pressure in the suction passage and continuing to act during such reduced pressure to enrich the mixture with such reduced suction.

3. In a carburetor, the combination of a suction passage having an air intake; a fuel passage communicating with the suction passage, the atmosphere and a source of fuel supply, said fuel passage delivering fuel to the suction passage; and devices varying the air supply to the fuel passage to vary the iiow of fuel, said devices being responsive to changes in pressure in the suction passage to enrich the mixture with a reduced suction..

4. In a carburetor, the combination of a suction passage having an air intake; a fuel passage communicating with the suction passage, the atmosphere and a source of fuel supply, said fuel passage delivering at least the major portion of the fuel to the suction passage; and devices varying the air supply to the fuel passage 'to vary -the flow of fuel, said devices being responsive to changes in pressure in the suction passage to enrich the mixture with a reduced suction.

5. In a carburetor, the combination of a suctionI passage having an air intake; a throttle valve; a fuel passagecommunicating with the suction passage, the atmosphere and a source of fuel supply, said fuel passage delivering fuel to the suction passage; and devices varying the air supply to the fuel passage to vary the iiow of fuel, said devices being responsive to changes in pressure at thedischarge side of the throttle to enrich the mixture as the suction is reduced. y

6. In a. carburetor` the combination of a suction passage having an 'air intake; a throttle valve; a fuel passage communicating with the suction passage, the atmosphereand a source of fuel supply, said fuel passage delivering at 'lea'st the major portion offuel to the suction passage; and devices varying the air. supply to the fuel passage to vary the flow of fuel, said devices being responsive to changes in pressure at the' discharge side of the throttle to enrich the mixa valve controlling the passage to the atture as the suction is reduced. mosphere; a spring resisting the opening of 7. In a carburetor, the combination of a the valve; and a pressure motor having one body having a suction passage; a throttle in side of its active element subjected to va- 5 the suction passage; a fuel well communiriations of pressure in the suction passage l5 eating with the suction passage above' the at the discharge side of the throttle acting on fuel level communicating with a source of said valve. fuel supply and communicating with the In testimony whereof I have hereunto set atmosphere; means for maintaining a conmy hand.

10 stant fuel level in the source of fuel supply; FREDERICK O. BALL. 

